CD177 and neoplasm: Regardless of their subtype based on TCRδ chain variant expression, γδ T cells can be distinguished in terms of functional potency based on their expression of cell surface receptors, including CD56 (16, 17), NKG2A (18), the SCART scavenger receptors (SCART1 and SCART2) (19), CD27 (20) and CD161 (21), signatures of which correlate with cytokine secretion and anti-tumor cytotoxicity.